The FDA has approved enzalutamide (Xtandi) to treat men with metastatic castration-resistant prostate cancer that has spread or recurred, even with medical or surgical therapy to minimize testosterone. Approved for patients with prostate cancer previously treated with docetaxel, enzalutamide was reviewed under the FDA’s priority review program. The drug received FDA approval 3 months ahead of the product’s prescription drug user fee goal date of November 22, 2012.
The safety and effectiveness of enzalutamide was evaluated in a placebo-controlled study of 1,199 patients with metastatic castration-resistant prostate cancer who had received prior treatment with docetaxel. The median overall survival for patients receiving enzalutamide was 18.4 months, vs 13.6 months for patients who received placebo.
The most common side effects observed with enzalutamide included weakness or fatigue, back pain, diarrhea, joint pain, hot flush, tissue swelling, musculoskeletal pain, and headache. ■